Ringing Phone ditector Circuit


Here I have introduced a ringing phone detector circuit.When people work in crowed areas they can't here when the phone is ringing.So this circuit will be useful circuit for you all








Part list

0.47uF 250V Capacitor (C1) = 1

10K 1/4 W Resistor (R1, R2) = 2

1K 1/4W Resistor (R3) = 1

20V 1/4W Zener Diode (D1, D2) = 2

1N4148 Diode (D3) = 1

2N3904 NPN Transistor (Q1) substitute: 2N2222 =1

4N27 Opto Isolator (U1) =1

Solid State Or Regular Relay = 1


Note
# Use lower voltage zener for D1 and D2.

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